This application claims benefit of Japanese Application No. 2000-224381 filed in Japan on Jul. 25, 2000, the contents of which are incorporated by this reference.
1. Field of the Invention
The present invention relates to an endoscope having an elongated insertion member and a control section and capable of undergoing at least one of cleaning, disinfection, and sterilization at high temperature.
2. Description of the Related Art
Today, endoscopes having an elongated insertion member thereof inserted into a body cavity in order to observe a deep region in the body cavity, or if necessary, having a therapeutic instrument used in combination in order to perform a cure or treatment are widely used in the field of medicine. For the medical endoscope, it is essential that a used endoscope should be reliably disinfected or sterilized.
In recent years, autoclaving (high-temperature high-pressure steam sterilization) has become a mainstream method of sterilizing medical equipment. This is because the autoclaving is not labor-intensive and low-cost. Besides, an endoscope can be reused immediately after being autoclaved.
Typical conditions for autoclaving are stipulated in the U.S. standard ANSI/AAMI ST37-1992 recommended by the American National Standards Institute (ANSI) and published from the Association for the Advancement of Medical Instrumentation (AAMI). According to the standard, a prevacuum sterilization process should be performed at 132xc2x0 C. for four min, and a gravity settling sterilization process should be performed at 132xc2x0 C. for ten min.
The conditions for autoclaving are quite severe for endoscopes. In order to realize an endoscope capable of being autoclaved under the above conditions, measures must be taken. Specifically, the endoscope must withstand high pressure, high temperature, and steam, though an endoscope reusable after being disinfected or sterilized according to any other method need not.
In particular, an insertion member of an endoscope that is a member to be inserted into a patient body is required to exhibit various delicate properties including flexibility and resiliency. The insertion member is more likely to deteriorate when exposed to high pressure, high temperature, or steam than a distal rigid part. Therefore, more sophisticated measures must be taken for the insertion member.
A conventional endoscope capable of being autoclaved is heated to have temperature of 130xc2x0 C. or more during autoclaving. After completion of the autoclaving, when the temperature of the insertion member thereof returns to room temperature, the endoscope is reused for endoscopic examination.
However, as far as the conventional endoscope capable of being autoclaved is concerned, after autoclaving is completed, a user must wear, for example, clean gloves so as to hold the insertion member with his/her hands for the purpose of checking the temperature of the insertion member.
After autoclaving is completed, a user holds the insertion member firmly with his/her hands so as to check the temperature of the insertion member. At this time, if the temperature of the insertion member is rather high, since the insertion member is soft, a sheathing resin coated over a soft flexible tube that is an integral part of the insertion member may be damaged or deformed.
Otherwise, a control section joined to the proximal end of the insertion member may be touched in order to check the temperature thereof. In this case, even if the temperature of the control section is low, the temperature of the insertion member may be still high.
Accordingly, an object of the present invention is to provide an endoscope making it possible to reliably and easily check if the temperature of an insertion member thereof has decreased to a level permitting use for examination without the necessity of holding the insertion member after completion of autoclaving.
Briefly, an endoscope in accordance with the present invention can undergo at least one of cleaning, disinfection, and sterilization at high temperature. The endoscope has an elongated insertion member, a control unit joined to the proximal end of the insertion member. A drop in the temperature of at least part of the outer surface of the insertion member occurring when the endoscope is cooled at predetermined temperature after being processed at high temperature is substantially equal to or larger than a drop in the temperature of at least part of the outer surface of any member other than the insertion member. Therefore, by holding at least part of the outer surface of any member other than the insertion member, it can be checked if the temperature of the insertion member has decreased to a level permitting use for examination.
An endoscope in accordance with the present invention. can undergo at least one of cleaning, disinfection, and sterilization at high temperature. The endoscope includes an elongated insertion member, and a control section joined to the proximal end of the insertion member. A drop in the temperature of at least part of the outer surface of the insertion member occurring when the endoscope is cooled at predetermined temperature after being processed at high temperature is substantially equal to or larger than a drop in the temperature of at least part of the outer surface of any member other than the insertion member.